Myth #1 High-rep workouts make your abs grow
Reality Your progress will plateau if you do the same exercises, regardless of reps
You need to intensify your workouts to teach your abs to stabilize your body weight. Add either more-challenging variations of body-weight exercises, or weighted abdominal exercises once the unweighted versions become too easy. Matt McGorry, C.F.T., a trainer at Peak Performance in New York City, recommends the triple plank. This combo—a front plank followed by a left-side plank and a right-side plank—forces you to contract your abs for long intervals, which helps carve your midsection. Start by maintaining each plank for 15 seconds, and work up to 60 seconds. When you hit that level, start adding sets, and rest only 30 seconds between them. If planks on the floor are too easy, put your feet on a small box.
Abs gadgets vs. the sit up
But don't forget: "No amount of abs work can take the place of a well-planned diet and a total-body workout," McGorry says. Abs don't start showing when you build them; they show when you've built all the muscles in your body and cut the fat around your midsection.
Myth #2 Abs workouts involve a lot of movement
Reality Exercises that require steadiness are best
When you bend your spine during crunches or situps, you risk injuring it, says Stuart McGill, Ph.D., a professor of spine biomechanics at the University of Waterloo, in Ontario. Doing those exercises isn't the best way to target your abs anyway, because you repeatedly bend the disks in your back and aren't forcing your abs to resist motion. That's why McGill suggests exercises that encourage spinal alignment and stability, such as planks. Your abs do all the work to keep you stabilized and lower your risk of back injury. (If you have back pain, see a physician before starting any abs regimen. Some abs exercises can make back problems worse.)
Rock hard abs in 5-steps
Exercises that prevent movement are especially good for building lateral abdominal strength, which is what helps your body stay in proper form under pressure (like when you play sports or do squats and deadlifts). McGill suggests the suitcase carry: Hold a heavy dumbbell in one hand and then walk increasingly long distances while maintaining perfect posture. This burns more calories than crunches do.
Myth #3 Rotational exercises are best for building your obliques
Reality Rotational exercises don't build obliques well and can harm the spine in some cases
Obliques surround and accentuate your abs and protect them from damage when you rotate your body quickly. So while exercises like the Russian twist can help build your obliques, they may not be the best way to build foundational strength, and they can force your spine to rotate under stress, says McGorry.
Instead, use heavy compound exercises—like squats and deadlifts—to make your obliques work harder to keep your spine aligned. For more challenge, add unbalanced moves—the single-leg lunge, for example, or a deadlift with one dumbbell. These types of exercises require your body to adjust to uneven stress while your spine is in its neutral position, which further stabilizes your core and builds your obliques (as long as you maintain proper form).